The invention relates generally to motor drive systems, and particularly to a motor drive system with bus voltage control.
Wide ranges of equipment, such as electric motor drive systems, are known and are in use for a variety of applications, such as in factory automation systems, power generation systems and so forth. Typically an electric drive is connected to a power source which provides electrical power to the load in a controlled manner. In alternating current (AC) motor drive systems, for example, electrical power is converted from an AC power source into direct current (DC) voltage via a converter. The DC voltage is then converted via an inverter coupled to the converter through a DC bus into AC voltage with controlled frequency, phase and amplitude which may be applied to drive the electric motor.
In certain motor drive systems, the magnitude of the bus voltage may be pre-determined for a particular motor and load combination based upon certain parameters such as AC power system voltage, load characteristics, velocity of the motor and so forth. Furthermore, the bus voltage of the DC bus is maintained as a constant value during operation of such systems. However, this may result in reduced efficiency of the motor drive systems. Further, power consumption of such systems may be substantial.
Accordingly, it would be desirable to develop a motor drive system with dynamic bus voltage control during operation of the system to enhance efficiency and reliability of such systems while maintaining or enhancing motion system performance.